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are making possible new types of television cameras and imaging devices based entirely upon solid-state components. Research on integrated image sensors has followed two experimental approaches: monolithic silicon and thin-film photoconductors. This article reviews the operation of the most common types of self-scanned sensors, indicating their relative advantages and disadvantages. Two new developments are a 256 × 256 element photoconductive sensor with integrated thin-film scanning decoders and a novel silicon photodiode sensor that may permit considerable reduction in element spacings. An IC medium-power voltage regulator. W. H. WILLIAMS and J. H. PARKER,IEEE Spectrum, February (1969), p. 72. This article describes a monolithic integrated-circuit voltage regulator for use in medium-power applications in the achievement of "local" or "on-card" regulation. Included are design features, an explanation of circuit's operation, a d.c. analysis, regulation analysis, performance characteristics, design rules and considerations, and selected applications.
A sinusoidal voltage-controlled oscillator for integrated circuits. A. B. GREBENE,1EEE Spectrum, March (1969), p. 79. This article describes an inductorless near-harmonic voltage-controlled oscillator circuit that utilizes a compensated Wien-bridge topology with a voltage-controlled Miller integrator as the tuning element. Suitable for monolithic integrated realization, the VCO offers a two-to-one control range for frequencies up to 10 MHz, with less than a 1-dB amplitude variation and less than a 10 per cent total harmonic distortion over the entire control range. Improved tantalum chip capacitors for hybrid circuits. D. E. MAGUIRE,Proc. 1969 Electron. Compon. Conf., Washington, D.C. 30 April-2 May (1969), p. 211. Tantalum chip capacitors are wellsuited for applications in hybrid circuitry. Previous limitations regarding their assembly, sealing, storage, and operating temperature ranges have been eliminated through the development of the high temperature solid copper counterelectrode system. Thus tantalum chips are now available and suitable for application in thin films/die bonded applications as well as the older thick film hybrid circuit construction. 7. SEMICONDUCTOR INTEGRATED CIRCUITS, DEVICES AND MATERIALS
Temperature: its measurement and control in semiconductor production. I. O. NmLSON, Instrum. Soc. Am. 5th Ann. Test Measurement Syrup. 1968 Proc., Vol. 5 (1968) paper 68-516. Production steps for integrated circuits, transistors and diodes using temperature as a parameter include: header manufacturing, crystal growing, epitaxial deposition, masking and diffusion, die attach, final assembly and environmental testing. Each of these steps is discussed and the temperature control systems described qualitatively. Recombinations via defects in degenerate semiconductors. E. L. HEASELL,Solid-St. Electron. 12 (1969), p. 225. It is shown that in degenerate materials, for a wide class of trap recombination models, it is possible to obtain the relevant capture rate equations by using a modified definition of the Shockley and Read trap parameters, n 1Pl, etc. Thus we may obtain recombination rate expressions, in terms of quasi-Fermi levels, by using the solutions that are already in the literature for non-degenerate recombination models. Silicon and gallium arsertide field-effect transistors with Schottky-barrier gate. H. STATZ and W. v. MUNCH, Solid-St. Electron. 12 (1969), p. 111. Field-effect transistors with Schottky-barrier gates have been produced using epitaxial layers of n-type silicon on p-type substrates, and n-type gallium arsenide on semi-insulating substrates. Some simple design considerations are presented and the fabrication processes are discussed in detail. Comparisons are made between two different device geometries and between silicon and gallium arsenide devices. Automatic IC dynamic testers. T. DREHERand D. JOHNSON,Solid St. Technol., March (1969), p. 31. Just as in the mid-fifties the computer customers forced solid-state manufacturers to make expensive switching-time measurements on transistors and diodes, so today's trends toward speed, more functions, and fewer ports are forcing pulse parameter testing into all phases of I.C. logic production and use. This article discusses design considerations of the present generation of automated pulse parameter
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test systems, with an eye toward the systems of the future. The authors see the present confusion concerning I.C. testing giving way to standardized, easily-specified, easily-repeatable switching-time measurements done on sophisticated high-speed machines built around a central computer.
Abrupt p-n junctions at arbitrary levels. H. D. BARBER, Solid-St. Electron. 12 (1969), p. 425. By introducing an injection level factor it is possible to obtain an approximate solution to the onedimensional transport equations through an abrupt p - n junction. Within its approximations, this solution is valid at levels of injection including the medium and high level cases. It is shown that this general solution yields the accepted forms for the limiting cases of low and high injection and is accurate to better than 20 per cent in the medium injection region. It is also demonstrated that an expression for the I - V characteristics of a p-n junction at arbitrary injection levels can be obtained by an analogue approach. These two expressions are compared using representative bulk parameters for silicon, germanium and indium antimonide and it is shown that the latter approach is generally accurate to better than 8 per cent. A complete analytic expression for the current voltage characteristic of a p+-n junction is derived and shown to describe experimental observations within the error of measurement.
Donor concentration dependence of electron-phonon scattering in antimony-doped germanium. H. J. ALBANY and G. LAURENCE, Solid St. Commun., 7 (1969), p. 63. The increase of the additional thermal resistivity at 6°K in the donor concentration range 8 × 1013 to 10 is cm-3 is observed to exhibit three concentration regions n < 1018 cm -~, --~1016 < n < ~ 3 × 1017 cm -3 and n > ~-~ 3 × 1017 cm -~, suggesting that electron-phonon scattering mechanisms other than those of Keyes and Carruthers should be considered in the low and intermediate concentration ranges.
Distribution of sodium in silicon nitride. I. FRANZ and W. LANGHEINRICH,Solid-St. Electron. 12 (1969), p. 145. The paper describes radiochemical examinations of the diffusion behaviour and content of sodium in single layer silicon nitride films and double layer silicon dioxide-silicon nitride films on silicon. The most significant result is that the sodium is gettered and enriched in the nitride in double layer films. Electrical properties of diffused zinc on SiO2-Si MOS structures. CHuN-YEN CHANG and KUEY-YEAu TSAO, Solid-St. Electron. 12 (1969), p. 411. Studies have been made on the C - V characteristics of SiO2-Si MOS structures under various oxidation temperature, heat treatment, and zinc doping conditions. Diffused zinc is expected to have three major effects on the characteristics of SiO 2Si MOS structures. Firstly, zinc behaves as negatively charged ion in SiO 2 layer which will compensate a positively charged ion such as a sodium ion. Secondly, zinc atoms behave as acceptor-like surface states at the SiO2-Si interface which may also compensate donor-like surface states at the interface. These two effects will cause the C - V curves to shift toward the positive-voltage direction. Thirdly, zinc atoms behave as shallow acceptors in the semiconductor substrate. These acceptors will change the background doping of the substrate which in turn causes a change of the normalized minimum capacitance. The above three effects have indeed been observed experimentally in both n-type and p-type silicon samples. C - V measurements of zinc diffused sample after three months room-temperature aging in air show that there are virtually no changes in comparison with those measured immediately after device fabrication.
Boundary conditions for the space-charge region o f a p - n junction. A. NUSSBAUM, Solid-St. Electron. 12 (1969), p. 177. The purpose of this paper is to show that the controversy concerning the relation of the applied potential difference to the difference across the space-charge region of a p-n junction is due to a neglect of the non-zero gradients of the electrochemical potentials. By incorporating these quantities and by a suitable modification of the Fletcher boundary conditions, the inconsistencies discovered by Van Vlietm and Gumme112~ can be removed. Kinetics and mechanism of thermal oxidation of silicon with special emphasis on impurity effects. A. G. REVESZand R. J. EVANS.ft. Phys. Chem. Solids 30 (1969), p. 551. Thermal oxidation of silicon was investigated under a variety of conditions. The oxidation follows a combination of linear and parabolic rate lows; the rate constants obey the Arrhenius relationship. Under very clean conditions